Color cinematography



April 13 1926.

P. D. BREWSTER COLOR CINEMATOGRAPHY Original Fil d M r h 3, 1918 3 Sheets-Sheet 1 INVENTOR.

April 13 1926. 1,580,114

P. D. BREWSTER 001.012 CINEMATOGRAPHY Original Filed March 23, 1918 5 Sheets-Sheet Q INVENTOR April 13 1926.

1,580,114 P. D. BREWSTER COLOR C INEMATOGRAPHY Original Filed March 25, 1918 3 Sheets-Sheet 5 Patented Apr. 13, 1926.

UNITED srATEs PATENT OFFICE.

PERCY D. BREWSTER, OF EAST ORANGE, NEW JERSEY.

oonon miu'roem nt.

Application filed larch 2d, 1918, Serial Ho. 224,140. Benewcd July 18, 1925.

To all/whom it may concern.

Be it known that'l, PERCY D. Bnnws'rnu, a citizen of the United States, residing at East Orange, Essex County, New Jersey, have in: 5 vented new and useful Improvements inl Color Cinematography, of which the following is a specification.

My present invention relates to a camera and printer mechanism for two color cine- 1 matography using two separate negative films and comprises special means for secur- -ing exact registry between the images onthe negative films. Q

The invention consists broadly in perforat- 1 ing the two negative films while they are at rest in the film gate or gates for making the exposure, the perforations being as near as possible to the position of the image photographed on the film and registering the two negative films, in relation to each other when printing the positive by means of these perforations. I

I am aware that cameras for black and white have been made in which the film was perforated in the film gate and registry with the positive when printing was secured by these perforations and also that it has been suggested to expose two separate films in two film ates and to print by contact on the two si es of a double coated; ositive film from the two negative films o tained, but

' Separate as the Geneva or Lumiere movements. The Geneva movement illustrated comprises the film sprocket 4 attached to the star wheel 5, driven intermittently by the pin wheel 6 in connection'with the camera driving mechanism. The films before being placed in the camera may be perforated in thestandard' manner, that is with four perforations per picture, or referably perforated with half the standar number of-perforations 7, 7, as shown in Fig. 4. Unperforated film may be used and can be fed into and from the film gate by suitable well known friction means. Preferably the film is passed through the film gate by .upper andlower feed sprockets having half. the usual number of teeth removed.

hotographio images are projected from t e lens 8 onto the emulsionson negative films 1 and 2 through difierent color filters so that simultaneously ictures from the same view point in two co ors-are made, that is, a series of negative images of one color-value on one negative film and anotherseries of negative images of the same object on the other film but of another colorvalue. The shutter 9 is adaptedto revent light from reaching the films while 1; ey aremoving. The light rays projected by the lens 8 onto splittlng prism 10 are divided by the silver strips on the surface 16 into two this process has been a failure to date due tovgloups one of which is reflected and the difficulties in registration and the object of this invention .is to provide 35 means for securing the necessary degree of registry. a My invention is illustrated in the accompanying drawing of which Fig. 1.is a lan view of the camera partly in section; igs. 2 and 3-arediagrammat1cal side elevations at right an les and parallel to the films reinsuperable spectively; igs. 4 and 5 illustrate different perforating systems; Fig. 6 s a section through a modified camera/using separate 55 outside, are fed intermittently through the film gate 3 by anywell known means, such- 1 and 2, with thesen sitized" other transmitted. The transmitted light passes through the red filter 13 and is reected by the prism or mirror 15 onto the film 2, while the reflected light rays pass throu h the blue-green filter 12 and are re-' flecte by the prism or mirror 12 onto film l. Adjusting means on the prism are provided to secure exact registry of the two pictures on the film. 1

While the two films are stationary in the film gate before, during or after the exposure is made, two holes 18, 18 are punched through both films exactly super osed, preferably by the same pair of' punches, and 10 cated as near the picture on the film asv pos sible. The" erforations may be locatel one on either si I eof the .in the margin in Fig. 4 or both perforations may be m one .margm as in Fig. 5, or located as desired.

Th Fig. two cuttingl holesfin t e film gate 3, th e punch being operated from the rocker'arm 20, which, in

punching mechanism illustrated in comprises the yoke 17, carrying the dies 19,19 which areguidedby .the two holes in the two films are superposed later in printing on both sides of the positive film, the images will exactly register. More than two holes may be perforated if desired or a single hole may be perforated and the two films guided on one side, however I prefer to punch two holes.

The same objects are attained in the camera illustrated in Fig. 6 in which the negative films l and 2 are fed intermittently through the separate film gates 25 and 26 respectively. Llght rays from the lens 8, controlled by shutter 27, are divided in a similar manner by the splitting prism 101l, the transmitted light being projected through the red filter 13 onto the film 2, while the reflected light is projected throughthe filter -12 onto the film l.

Film gates and 26 are provided with yokes 28, 28 carrying the cuttting dies 29, 29 guided in the film gate. An electrical method using. solenoids is shown ,for operating the punches, comprising the solenoids 30, 30 having cores made in two parts, nonmagnetic part 32 being attached to the yokes, while the magnetic portion 31 is mounted so as to be drawn into the coil when itis magnetized. Springs 33, 33-are adapted to withdraw the dies. Current for the solenoids is supplied by battery or enerator 34 and their actions are controlled y the insulated commutator 36, operating for convenience on shutter shaft 38, carrying the metal segment I 37. grounded on the shaft so that when this segment comes in contact with the brush 35, the circuit is closed erate. I

Any type of mechanism, electrical or mechaaiical, for operating the punches may be use In this; type of camera either one of two general adjusting means are necessary for the two pictures are originally not in registry nor are the perforating dies necessarily and the punches op- I in perfect alignment with each other. so that provision must be made for adjusting one set of dies in relation to the other or by adjusting the images so that .they will have exactly the same relation to the punches, which are fixed in place. lln Fig. '2' the punch block 38, carrying the yoke 28 and dies 29, 29 as well as the film aperture is mounted to turn in the block 40, controlled by capstan screw 41, the block may be adjusted vertically by means of stops and admoon. 14

justing screws 43, 43 and horizontally by means of screws 42,42. The block is drilled with ample clearance holes for screws 41, 41 and held in place by washers on said screws.

To test for registry a pair of pictures, preferably made simultaneously, are superposed with a pair of pins of proper size in the perforations and the registry of the images examined preferably with a low power microscope and. any error in registry measured and compensated for with the adjustments provided.

If registry is to be made by optical means, the pair of perforating dies are set as nearly true as possible and fixed permanently in place and provision is made forshifting the image. Referring to Figs. 9 and 10 the splitting prism 1011 is mounted'on the disk 67 adapted to turn on pin 72 in the camera base plate 68 on the point of intersection of the axial ray from the lens and the splitting surface of the mirror horizontal, its movement being controlled by the capstan screw 69 and its vertical movement by the jam screws 70 and 7 3 tapped into disk 67 and bearing against base 68, the disk being held in place by screws and washers 71 and 74. Clearance holes in disk 67 for screws 71 and 74 are ample to permit the very slight movement required for horizontal adjustment. With these means any error in registry of the images can be corrected and a series of pairs of images secured that exactly register when pins are in their relative perforations.

Positive prints of several different types may be made from these negatives, for example a single coated positive film may be perforated to conform to the negative film perforations, and printed ,in contact with one negative, the images developed and properly colored and waterproofed and another emulsion coated on top or on the other side and the positive film again printed from properly corresponding pictures on the other negative, the images, developed and colored to form the finished print. A second method is to use film coated on both sides with light-sensitive positive emulsions perforated to correspond with the master perforations on the negative films, print on one side from one negative in contact, registering by means of the perforations, and then from the other negative film on the other side again registering by the perforations, develop the images and color them on the two sides in the proper colors.

However, I prefer to print simultaneously on the two sides of a double coated positive film from the two negative films. This positive film may be perforated to correspond with the master perforations on the ne ative films and registry secured by passing a pin through the three films or th positive tive films to pass through the film mayuse the standard perforations and allow the registering pins for the two nega rforations.

The printer illustrated in Fig. 11 shows the two negative fihns 1 and 2 and double coated positive film 50, drawn from their .containers and looped by sprocket 'or action of lights 59 and 60 respectively, the

,located "while the films are at rest in the camera to action of the light being controlled by the shutters 61 and 62 adapted to rotect the films when they are moving. efore the film is exposed ut after coming to rest, the

pins 63 in yoke 65, driven by the drunken screw 66, are forced into the master perforations'in the two negativefilms at least or all three films and the negative images superposed, it being understood that the positive film has erforations into which the pins fit. The plns are withdrawn before.

the films start to move after the exposure. If desired the film gate may be constructed to separate slightly whens the films are moving and to press together before the ex posure is made. I then develop the images on the two sides of the' film in the ordinary way and convert the silverimages tov dye images by any well known means.

I claim I 1. In the art of two-color cinematography, the improvement comprising projecting in a. suitable camera images of the object upon two separate negative films in light of different colors for the production of a'series of negative images'of one'color-value on one film and a series of negative images of the other color-value, on the other film, perforat ing the two negative films at definitely ints with respect to the images produce registry perforations, printing one series ofjma s on one side of a positive film sensitize on bothsides and printing the other series ofimages on the other side of the positive film, and registering the images on one side with the respective images on the other side by registry pins passing through perforations in t 1e positive film and through the aforesaid registry perforations in the negative film from which the printing is being effected.

2. In the art of two-color cinematography, the improvement comprising ojcting images of the object in light o different colors upon two separate films, and perforating the two films at points definitely and similarly located relatively to the respectiveimages while the films are at rest.

3. In the art of two-color cinematography, the improvement comprising projecting simultaneously and from the same viewpoint two images of the object upon two separate films, and cutting a plurality of perforations in both films at points having exactly the same location 'relative to the respective images.

4. In the art of two-color cinematography,-

the improvement comprising projecting two separate images of the object upon two separate films, and perforating the two films on each side of the image and at exactly corresponding points on the two films while the same are at-rest.

v5. In the art of two-color cinematography, the improvement comprising dividing the light from the object into two groups, projectin the two groups through appropriate colorlters upon two separate negative films in a suitable camera for the production of. separate color-value negative images, perforating the two negative films at definitely located points relative to the respective images while the films are at rest in the camera to produce registry perforations, and in rinting from such negatives utilizing the said master perforations to receive registry pins to register the respective images on opposite sides of a positive film.

In testimony whereof, I have signed my name to this specification this 22nd day of -March, 1918.

" PERCY D. BREWSTER. 

